How can I determine correct pinch attributes for zomming?

Asked by Alexander Betaev on 2014-02-28


I am trying to configure pinch to zoom in Firefox. For that I use pinch attribute "radius delta". But I found that radius delta is relative. It is between 0 and 1 (actually the least number is about 0.5) when radius shrinks, and greater than 1 (did not see a number more than 1.3) when it grows. However radius delta in example wish XML is in [20:40] and [-40:-20] ranges, which seem to be absolute values.
I am a little bit confused by that and I cannot configure more or less smooth zooming. Using example ranges lead that only zoom works.

Thanks in advance.

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English Edit question
ginn Edit question
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Stephen M. Webb (bregma) said : #1

I think the problem comes from the fact that Ginn (and its example wishes file) was written to use Geis 1.0, and there were some significant changes to the underlying recognition software when Geis 2.0 came out. I believe one of those changes was that the radius delta became a ratio rather than an absolute quantity in input device coordinates, since touchpad device coordinates seldom make sense in a window context.

At this point, I suggest experimentation to find the right values for your use is the best approach, since none of the values are actually documented yet.

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